With a known circular saw arrangement of this type (German Patent No. 1 628 992), the support element has the shape of a round table which is inserted into an opening in the table plate and is held rotatable in this opening. The saw unit is mounted at an edge area of the round table so that in the first position of the table plate it can be pivoted about a horizontal axis. In this way chop-cuts can be carried out with the saw blade usually powered by an electric motor, the saw unit being lowered by the user from a position in which the saw blade is located at a distance above the round table, and the saw blade thus being guided though the workpiece to be cut. So that the workpiece can be completely separated, a through slot is provided in the round table, through which slot the lower section of the saw blade extends in the lowered position, so that in this way the workpiece resting on the first side of the round plate and the associated surface of the round table can be completely separated.
To set mitre cuts, the round table can be rotated about its rotation axis, the saw unit mounted to it being correspondingly rotated. The saw blade is thus moved into the desired mitre position with regard to the workpiece-positioning face of a fence arrangement, which for such a type of chop-cut operation is usually mounted at the first side of the table plate.
When the table plate located in its first position is released from its connection with the frame, rotated through 180.degree. into its second position and once more securely connected to the frame, the saw unit can be pivoted into a position in which the saw blade extends from below through the through slot over the upper surface of the second side of the table plate. The saw unit can be locked in this sawing position with regard to the table plate and additionally, usually in the plane of the saw blade, a riving knife secured and a protective cover affixed, so that the circular saw arrangement can then can be used like a type of circular saw bench.
One problem with the known circular saw arrangement is that in the first position of the table plate the attainable cutting width is essentially limited by the dimensions of the round table containing the through slot for the saw blade which is to be lowered. To achieve a larger cutting width it would be possible per se to enlarge the diameter of the round table and then to also use a saw blade with a larger diameter. However, this leads to an enlargement of the dimensions of the circular saw arrangement, because, inter alia, the table plate bearing the round table must then likewise be enlarged in order to provide sufficient stability to mount the round table carrying the saw unit.
To at least partially avoid this limitation of the cutting width with the known circular saw arrangement, slots have also already been provided in the table plate, of which the one in the centre position of the saw blade forms a continuation of the through slot provided in the round table, whilst others form a corresponding continuation of this through slot for selected mitre positions, say mitre positions of 45.degree.. In this way it was then possible, at least in the centre position and the marked mitre positions, to cut though wider workpieces by lowering the saw blade more than in the other mitre positions.
However, this structure which enlarges the cutting width in exceptional cases, leads, on the one hand, to the weakening of the table plate because of the slots in it, so that said table plate must be constructed with greater strength or to larger dimensions. On the other hand, design features must be provided by means of which, in mitre positions in which no elongation in the table plate is available for the through slot, the saw unit can certainly be prevented from being lowered so far that the saw blade engages with the edge area of the table plate. The design outlay needed to achieve somewhat enlarged cutting widths in a few selected positions of the saw blade is therefore considerable. Moreover, the cutting width always remained limited by the dimensions of the saw blade.